1. Field of the Invention
The present invention relates to an ink sheet cartridge, and more particularly, it relates to an ink sheet cartridge mounted on a printer.
2. Description of the Background Art
An ink sheet cartridge mounted on a printer is known in general, as disclosed in Japanese Patent Laying-Open No. 6-183087 (1994) or 6-199388 (1994), for example.
The aforementioned Japanese Patent Laying-Open No. 6-183087 describes an ink sheet cartridge comprising upper and lower shell halves rotatably storing a feed bobbin wound with an ink sheet and a take-up bobbin taking up a spent ink sheet respectively. A first end of the upper shell half is attached to a first end of the lower shell half in an openable/closable manner with a hinge, and the upper and lower shell halves are assembled with each other by engaging a hook provided on a second end of the upper shell half with an engaging hole provided on a second end of the lower shell half. In this ink sheet cartridge, protrusions are provided on both side ends of the upper and lower shell halves respectively. Separately formed holding members are fitted with the protrusions of the upper and lower shell halves assembled with each other, thereby suppressing disassembly of the upper and lower shell halves.
The aforementioned Japanese Patent Laying-Open No. 6-199388 describes an ink sheet cartridge comprising upper and lower shell halves rotatably storing a feed bobbin wound with an ink sheet and a take-up bobbin taking up a spent ink sheet respectively. A separately formed cover is mounted on the ink sheet cartridge for fixing the upper and lower shell halves to each other.
An ink sheet cartridge employed for a thermal transfer printer is also known in general. FIG. 16 is an exploded perspective view of a conventional ink sheet cartridge 100 employed for a thermal transfer printer. FIG. 17 is an overall perspective view of the conventional ink sheet cartridge 100 employed for a thermal transfer printer. FIG. 18 is a sectional view taken along the line 200-200 in FIG. 17. The structure of the conventional ink sheet cartridge 100 employed for a thermal transfer printer is described with reference to FIGS. 16 to 18.
The conventional ink sheet cartridge 100 employed for a thermal transfer printer comprises upper and lower components 102 and 103 of resin constituting a bobbin case 101, as shown in FIG. 16. The bobbin case 101 stores a feed bobbin 105 feeding an ink sheet 104, a take-up bobbin 106 taking up the ink sheet 104 and helical compression springs 107 for urging the feed bobbin 105 and the take-up bobbin 106 toward a first end of the bobbin case 101. Separately formed holding members 108 of resin are attached to both outer surfaces of the bobbin case 101 for holding the upper and lower components 102 and 103 in a state fixed to each other, as shown in FIGS. 16 and 17.
The upper component 102 constituting the bobbin case 101 includes a feed bobbin storage portion 102a storing the feed bobbin 105, a take-up bobbin storage portion 102b storing the take-up bobbin 106 and coupling portions 102c and 102d coupling the feed bobbin storage portion 102a and the take-up bobbin storage portion 102b with each other, as shown in FIG. 16. Protrusions 102e extending in parallel with the extensional direction of the feed bobbin storage portion 102a and the take-up bobbin storage portion 102b are provided on both outer surfaces of the upper component 102.
The lower component 103 constituting the bobbin case 101 includes a feed bobbin storage portion 103a storing the feed bobbin 105, a take-up bobbin storage portion 103b storing the take-up bobbin 106 and coupling portions 103c and 103d coupling the feed bobbin storage portion 103a and the take-up bobbin storage portion 103b with each other, as shown in FIG. 16. The feed bobbin storage portion 103a is provided therein with a feed bobbin support portion 103e rotatably supporting the feed bobbin 105, while the take-up bobbin storage portion 103b is provided therein with a take-up bobbin support portion 103f rotatably supporting the take-up bobbin 106. Protrusions 103g extending in parallel with the extensional direction of the feed bobbin storage portion 103a and the take-up bobbin storage portion 103b are provided on both outer surfaces of the lower component 103.
The feed bobbin 105 is provided with a sheet feed shaft 105a wound with the ink sheet 104, a flange 105b, a drive shaft 105d and a driven shaft 105d, as shown in FIG. 16. The take-up bobbin 106 is provided with a sheet take-up shaft 106a taking up the ink sheet 104, a flange 106b, a drive shaft 106c and a driven shaft 106d, as shown in FIG. 16. Each of the holding members 108 has a U-shaped section, as shown in FIGS. 16 to 18.
A method of assembling the upper and lower components 102 and 103 of the conventional ink sheet cartridge 100 employed for a thermal transfer printer is now described with reference to FIGS. 16 to 18. First, the helical compression springs 107 are set on the driven shafts 105d and 106d of the feed bobbin 105 and the take-up bobbin 106 respectively, as shown in FIG. 16. Then, the feed bobbin 105 and the take-up bobbin 106 are arranged to be supported by the feed bobbin support portion 103e and the take-up bobbin support portion 103f of the feed bobbin storage portion 103e and the take-up bobbin storage portion 103b of the lower component 103 respectively. Thereafter an adhesive is applied to contact surfaces of the upper and lower components 102 and 103 coming into contact with each other when the upper and lower components 102 and 103 fixed to each other. More specifically, the adhesive is applied to contact surfaces of the coupling portions 102c and 102d of the upper component 102, those of the protrusions 102e provided on both side surfaces of the upper component 102, those of the coupling portions 103c and 103d of the lower component 103 and those of the protrusions 103g provided on both side surfaces of the lower component 103 respectively. The upper and lower components 102 and 103 are so butted to each other that the contact surfaces thereof come into contact with each other. Thereafter the holding members 108 coated with an adhesive are fitted with the contact portions between the protrusions 102e and 103g of the upper and lower components 102 and 103, as shown in FIGS. 17 and 18. Thus, the upper and lower components 102 and 103 of the ink sheet cartridge 100 are fixed to and assembled with each other.
In the conventional ink sheet cartridge 100 shown in FIGS. 16 to 18, however, the upper and lower components 102 and 103 are held in the fixed state by fitting the separately formed holding members 108 of resin with the protrusions 102e and 103g provided on both side surfaces of the ink sheet cartridge 100, and hence the holding members 108 are disadvantageously necessary in order to fix the upper and lower components 102 and 103 to each other. Thus, the number of components is disadvantageously increased. In the conventional ink sheet cartridge 100 shown in FIGS. 16 to 18, further, the upper and lower components 102 and 103 are fixed to each other with the adhesive and thereafter held in the fixed state with the holding members 108, and hence the adhesive is disadvantageously necessary.
In the ink sheet cartridge disclosed in the aforementioned Japanese Patent Laying-Open No. 6-183087, on the other hand, the separately formed holding members must be fitted with the protrusions provided on the upper and lower shell halves respectively in order to suppress disassembly of the upper and lower shell halves, and hence the number of components is disadvantageously increased.
In the ink sheet cartridge disclosed in the aforementioned Japanese Patent Laying-Open No. 6-199388, further, the separately formed cover must be attached in order to fix the upper and lower shell halves to each other, and hence the number of components is disadvantageously increased due to the provision of the cover.